Not having any plans for the weekend, Tristan and I agreed to meet up in Zurich-Wiedikon for a steam train ride organized by the Zuricher Museumsbahn down to Sihlbrugg and back with a long layover in Sihlwald. This route mostly follows the SZU Sihltalbahn (S4) with exception of the tunnel between Wiedikon and Bahnhof Giesshuebel, which gets used only by occasional freight trains coming up this route and on to bypass Zurich main station.

Arrival in Sihlwald. The grill is ready to feed hungry travelers.

Most of the trip leads through suburbs of Zurich, and, while nice, is actually not that impressive (well, with the exception that we are RIDING IN A STEAM TRAIN! YAY!)

It gets pretty between Langnau-Glattikon and Sihlwald, and really scenic between Sihlwald and Sihlbrugg.

Sihlbrugg is a junction with the regular main line that runs south from Zurich along Lake Zurich via Thalwil to Zug and Luzern. Early in the video Schnaaggi Schaaggi is running around our train in Sihlbrugg while an IR to Luzern is greeting it from the main line. It was fascinating to see this juxtaposition of "our" little steam engine and the modern electric passenger trains that dominate the Swiss railway system. Similar encounters repeated throughout the trip, thanks to the very dense and busy Swiss passenger rail system.

Sihlbrugg: Ready to return to Sihlwald

Sihlbrugg is a popular starting point for hikers. There are several routes to choose from that eventually lead to Sihlwald or further up the Sihltal where they can take S4 back to Zurich.

We took the steam train back to Sihlwald and watched servicing of the locomotive for a while.

While Tristan wasn't too pleased with the offerings at the grill, I got myself a sausage with bread, and enjoyed the view.

Eventually the locomotive service crew came over as well, grabbed food and drinks, and had their lunch, too.

Just as we were starting to get bored, the locomotive came back to the train and the crew prepared for the return trip to Zurich.

I'm impressed by how the steam train schedule is part of the regular Sunday schedule, even though the train only runs on the last Sunday of the month in the summer. Most of this line is single-track, so meets between S-Bahn and steam train are built into the schedule in a way that maintains punctuality for the S-Bahn.

Back a Wiedikon, the locomotive had to run around the train again for the last trip to Sihlwald. Because of the busy S-Bahn schedule they really had to hurry up to get to the other end of the station. The video has this scene starting at 6:50.

I hung out on the platform until the train departed and got to watch more servicing, while the pressure relief valve lets off steam.

The steam train of Museumsbahn Zurich "Schnaaggi Schaaggi" made it's first trip this year while I was in Zurich. I missed the chance to ride the train the last couple years, but this time the stars aligned.

Friday, April 24, 2015

Tonight Balazs invited me to an operating session on his office layout. I wrote about an earlier version of this layout before.

The last train of the day has arrived in a staging siding on the window sill.
The siding is named after the software engineer whose desk is right next to it

By necessity this layout is purely operations oriented, uses sectional track on office furniture and window sills. It packs a lot of fun into a minimal amount of space. Balazs and Isabella added humorous touches by naming the various trains, stations and industries after work-related tools and processes. E.g. a train might come from staging ("The Internets" or "Offsite"), travel across the layout past the loop with a village on a glass shelf ("Glastown Loop"), have work to do at some industries named after product areas or source code revision tools we use daily, loop across the layout past the Godzilla figurine ("Godzilla Loop") and terminate at the central yard ("MTV").

Half a dozen operators were kept busy for several ours and we left the office well past midnight. It seemed like everyone had a good time.

Switzerland started electrification of their railways much earlier than the rest of Europe, so not surprisingly there is a wide selection of early heavy electric locomotives at the Verkehrshaus.

This early generation electric switcher locomotive used a single, large electric motor which is connected directly to the side rods by a diagonal rod. Notice the various counter weights on the axles.

A few years later, when the Ce6/8 II was built, technology had advanced quite a bit. The heaviest part of an electric locomotive is the transformer used for conversion of catenary voltage to something more agreeable for the electric traction motors. In the "Crocodile" design the transformer sits on the bridge frame in the middle of the locomotive, while the motors and supporting electric are in the narrow hoods whose trucks are short-coupled under the bridge frame.This arrangement contributes to the Crocodiles excellent ability to navigate tight curves in the Swiss mountains.

Power is transferred to the wheels using blind axles and a unique driver rod arrangement that allows each axle to move in its suspension without twisting the rods, affecting suspension of the other axles, or reducing efficiency of traction. The obvious drawback of this arrangement is how complicated it is. A later series of the crocodile (the Ce 6/8 III, prototype for a popular Maerklin model) used a simplified transmission technique ("Wintherthurer Schraegstangenantrieb").

Cab of Ce 6/8 II

Another variation of the theme was used in BLS Be 5/7.

The electric motors drive 2 blind axles which are coupled to side rods using a triangular connecting rod.

The "Landi-Lok" Nr. 11852 presented at the national fair of Switzerland ("Landesausstellung") in 1939 shortly before World War II was a massive design and is still the the most powerful locomotive of SBB with over 8000 kW. It consists of two locomotive frames coupled back to back, each containing 8 traction motors driving 4 of the 7 axles on each half. The locomotive is so powerful that SBB never used its full capabilities because it would break the train couplers.

Landi-Lok. It's so big that I couldn't get a complete, unobstructed photo.

The Landi-Lok is one of the few locomotives one can go inside. The machine room with some oft the traction motors visible is impressive, but must have been even more impressive with all the machinery in operation.

Standing in the pit below the tender of Nr. 2965 I finally really understood how the linkage works so that brake shoes grab a wheel from both sides as the linkage is actuated by the brake cylinder. There's nothing better to really understand than looking at the original.

As I was under the locomotive marveling at the construction I noticed the odd arrangement of drive axle number 2. It's a cranked axle. Here's a picture of cranked axle outside the locomotive.

Cranked axles are used on steam locomotives that have cylinders inside the frame in addition to the easily visible outside cylinders connected to the driver rods driving the wheels. The pistons of the inside cylinders connect to the cranked axle. Other examples of locomotives with inside cylinders are the German BR18.3 (for balanced moving weights at higher speeds) and BR44 (for more pulling power).

Cranked axle with cylinders and pistons inside the locomotive frame. Looking towards the front of the locomotive.

Inside cylinders and pistons. Looking straight up.

Looking back at axle 2, the connecting rods to the pistons and how they connect to the axle are readily visible.

For the last picture I stuck my phone camera inside the locomotive frame to catch a photo of the inside cylinder fronts.

Inside cylinder heads looking back from just above the locomotive frame